Project profile :Due to the design defects of the steam turbine shaft sealing system in Wuhan Zhuankou Gas Turbine Power Plant, as the operation time gets longer, the defects become more and more serious, the system needs to be modified to eliminate the safety hazard. After the site survey and comprehensive evaluation and analysis of the operating system under different operating conditions, we adopted a targeted technical transformation plan, modified the shaft sealing system. Finally we solved the air and steam leakage problem of steam turbine shaft sealing system and lube oil emulsification problem.